Studies on Deeper Rotary Tillage (III)

Field Test (II) Tilling Load Characteristics and Analysis of Throwing Tilled Soil

Abstract

Field test on deeper rotary tillage by down cut tilling and up cut tilling was conducted on clay soil and sandy soil to confirm the characteristics of tilling torque, specific tilling energy and rear axle torque of tractor. The characteristics of throwing of tilled soil were also analyzed. Results were as follows.
1) Both down cut tilling under the depth smaller than rotor radius and up cut tilling under the depth deeper than rotor radius with higher revolutional speed gave less tilling torque and specific tilling energy. The latter may be favolable for deeper rotary tillage.
2) Tilling torque and specific tilling energy became larger, when throwing of tilled soil became inferior and most of tilled soil was cut again.
3) Tilling torque and specific tilling energy by tillage in clay soil were much larger than that by tillage in sandy soil, and this was more evident when throwing of the soil was superior.
4) Rear axle torque of tractor by up cut tilling was much larger than that by down cut tilling and the torque at tilling in clay soil was smaller than that in sandy soil.
5) Throwing model of tilled soil was proposed and it will be usefull to analyze the throwing of tilled soil in field operation.
6) From the analysis with the model, it was found that soil clods produced from the cutting of untilled soil fell down to the bottom and those produced from the cutting of tilled soil were thrown backward.
7) It is important to improve the throwing performance at cutting of untilled soil for avoiding the repeated cutting.